dma_buf_end_cpu_access(9)

📦 version 7.3.1, in nixpkgs unstable

💖 dma_buf_end_cpu_access(9) — the Kernel API Manual glow-up ✨

okay so bestie, we're in the Kernel API Manual today and this page is all about the closing move of a CPU access arc. she's the sequel, the cooldown, the "ok we're done here" text. let's get into it 🫶

🌸 NAME 🌸

dma_buf_end_cpu_access — the function you must call after you've been accessing a dma_buf from the cpu in the kernel context. she calls end_cpu_access so the exporter can do its own little exporter-specific actions 💅

and a very important vibe check: coherency is only guaranteed in the specified range, for the specified access direction. no cap. don't go thinking you get coherency everywhere for free 🙈

⭐ SYNOPSIS ⭐

int dma_buf_end_cpu_access (struct dma_buf *dmabuf , enum
dma_data_direction direction );

look at her. iconic signature. returns an int like the main character she is 👑

🎀 ARGUMENTS 🎀

  • dmabuf [in] — the buffer you're completing cpu access for 💖
  • direction [in] — the direction of access 🌈

two args, both [in], both important, periodt.

🦋 DESCRIPTION 🦋

so this is literally the terminator of the pair — it ends the CPU access that you started with dma_buf_begin_cpu_access. think of it as closing the tab, logging out, saying bye to the group chat 😭

she can return negative error values, and she returns 0 on success ✨

lowkey do not ignore a negative return here bestie, that's the function telling you something went sideways 💀

👑 SEE ALSO 👑

the kernel file lives at ./drivers/dma-buf/dma-buf.c, and here's the whole friend group — every single one of them, no skips:

and that's the whole page, bestie 🧚💜 this one's out of ./drivers/dma-buf, dated October 2026, and yes she signed off as dma_buf_end_cpu_access(9) — main character energy from top to bottom, as she should 💅✨

📦 where this page comes from